Blower



G. W. ALLEN Patented May 10, 1927.

UNITED Is fATEs PATENT OFFICE.-

GEORGE W. ALLEN, OF HYDE PARK, MASSACHUSETTS, ASSIGNOR T0 B. F. STUBTE- VANT COMPANY, OF

CHUSETTS.

HYDE PARK, MASSACHUSETTS, A CORPORATION .OF MASSA- BLOWER.

Application filed August 18, 1923. Serial No. 658,132.

The present invention relates to blowers and more particularly to centrifug'alblowers in which air or other fluid is taken in axially and discharged eircumferentia-lly.

The object of the. invention is to provide a wheel for blowers of this general type which will be of strong mechanical construction and re latively simplein manufacture and adapted for operation at high speeds.

lWith this object in view, the invention consistsof certain novel features of construction, combinations and arrangements of parts hereinafter described and particularly defined in the claims.

In the drawings Figure 1 is an elevation of a blower wheel embodying the several features of the present invention, certain of the parts being broken away; Fig. 2 is a section on line 22 of Fig. 1; Fig. 3 1s a section, online 33 of Fig. 2; and Fig. 4 is an end'view of one of the floats looking toward the center of the wheel.

The illustrated embodiment of the invention comprises a series of floats indicated generally at 6 which are mounted between a pair of annular side plates 8 and upon a solid central forged disk 10 which is provided with an integral hub 12 bored to receive the driving shaft. The side plates 8 are of the usual form, each being preferably pressed out of a single piece of sheet metal and arranged to converge toward each other at the outer periphery, as shown in Fig. 2. In order to avoid excessive strains and stresses at the periphery of the disk 10 which would be developed at the high rotational speed of operation of this fan, the diameter of the disk is made substantially less than that of the complete fan wheel, being, in the illustrated embodiment of the invention, about three-fourths of such diameter. The disk is also formed with a slight taper from hub to periphery. It will be obvious that due to the use of the solid supporting disk the illustrated wheel is adapted to take in air from both sides and is therefore to be employed in a blower casing having an iiilet at each side. In order to form a rigid construction, each of the side plates is provided with a binder ring 14 adjacent the iiilet opening.

Each float 6 consists of a pair of blades 16, each blade having its inner side edge, i.

e. the side edge adjacent the disk 10, extended inwardly towards the axis well beyond the outer side edge, thereby affording additional strength and support to the blade without reducing the diameter of the intake opening. Further strength and rigidity is afforded by the curvature of the blades transversely ofthe axis of rotation as shown in Fig. 1 and by the opposite longitudinal curvatures at the inner and outer ends ofth'e blade.

The longitudinal curvature of the inner portion ofthe blade is convextoward the direction of movement as shown in Fig.

3 and that of the outer portion of the blade is concave toward thedirection of movementas shown in Fig.4. Each blade is provided with an outer forwardly extending flange or lip 18 for attachment to its corresponding side plate a row of rivets 20, and an inner rearwardly extending flange 22 for attachment to the central diskby a row of rivets 24. As indicated in Fig. 2, the same row of rivets 24 is employed to attach both flanges 22 of the pair of blades to the disk 10. It is desirable that GOIIGSPOHdlDg pairs of blades 16 be positively secured together outside the periphery of the disk 10. To this end, the opposing flanges 22 of each pair of blades are welded together from the point where they project from the edge of the disk 10 to the edge of thewheel. As indicated in the drawings, the tapered disk 10 is such as to bring the outer ends of the flanges 22 normally close together so that the welding operation may be readily carried out, the space between the flanges being filled with the weld, as indicated at 26, in such a manner that a solid rigid float is obtained from each pair of blades. In order to provide further reenforcement for the wheel, a metal angle 28 is connected to the frontof each blade and to the disk by rivets 30.

It will be seen that the present invention provides a wheel which comprises few parts, may be easily constructed at a comparatively low cost, and is of exceptional strength. It is particularly adapted for high speed drive as by a direct connected steam turbine.

lVhile it is preferred to employ the specific construction and arrangement of parts claims, and may be changed or modified without departing from the broader feature of the invention.

Having thus described the invention, what is claimed is:

1. A blower wheel comprising a pair of annular side plates, having large central openings for admission of air, a solid rotatable central disk between the side plates of a diameter less than the outer diameter of the side plates and greater than their inner diameter, and a series of floats having flanges at their ends riveted to the disk and to the side plates, the inner portions of the floats and the flanges thereon adjacent the disk extending inwardly beyond the inner margin of the side plates and near the center of the disk to provide additional riveting surfaces to the disk without obstruction of the air admission openings of the side plates.

2. A blower wheel comprising a pair of annular side plates, a solid central disk between the plates and of an external diameter less than that of the side plates, and floats secured to the plates and to the disk and extending outwardly beyond the periphery of the disk and inwardly beyond the inner margin of the side plates, the floats being longitudinally curved and without substantial transverse curvature for the major portion of their length and transversely curved at their inner ends.

3. A blower wheel comprising a pair of side plates, a solid central supporting disk of less diameter than the side plates, a series of floats each consisting of a pair of blades and means for securing the blades to the plates and to the disk, each blade having its inner portion transversely curved and its inner and outer portions of opposite longitudinal curvature, respectively convex and concave toward the direction of movement.

4. A blower wheel comprising a pair of annular side plates having large central openings for admission of air, a solid rotatable disk between the side plates of a diameter less than the outer diameter of the side plates and greater than their inner diameter, a series of blades having flanges at each end for attachment respectively to the plates and to the disk, the inner portions of the blades and the flanges thereon adjacent the disk extending inwardly beyond: the inner margin of the side plates and near the center of the disk for attachment to the disk without obstruction of the air admission openings of the side plates, and an angle piece secured to the disk and to each blade and extending in an opposite direction from theflange thereon to form a supplementary oppositely turned flange to provide additional riveting surface for securing the blade to the disk.

GEORGE W. ALLEN. 

